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11.
E P A Lopes E C Gouveia A C C Albuquerque L H B C Sette L A Mello R C Moreira M R C D Coelho 《Journal of clinical virology》2006,35(3):298-302
BACKGROUND: Elevated liver enzymes are infrequent in patients with hepatitis C virus (HCV) infection undergoing chronic hemodialysis (HD), suggesting that the alanine aminotransferase (ALT) is a poor predictor of hepatocellular damage in this population. OBJECTIVE: To establish a more appropriate cut-off value of ALT to identify biochemical activity due to HCV infection in HD patients. STUDY DESIGN: A total of 217 patients, with an average age of 51.2 years, were evaluated between January and October 2002; 130 were males (60%). Serum ALT was measured by a kinetic method in five consecutive monthly blood samples, from which an average was obtained and divided by the upper limit of normal (ULN). HCV antibodies were determined using an enzyme immunoassay, the serum HCV-RNA by nested-PCR and HCV genotype by hybridization of the amplified sequence from the 5'-non-coding region. The cut-off value of ALT was obtained from a ROC curve. RESULTS: Within the 217 patients, 18 (8.3%) were anti-HCV-positive, 17 (7.8%) of whom were also HCV-RNA-positive. Genotype distribution was: 1a=47%; 1b=18%; 3a=35%. Mean ALT/ULN (0.77+/-0.57) of the 18 anti-HCV-positive cases was higher (p<0.001) than the negative group (0.38+/-0.23). The mean ALT/ULN (0.81+/-0.57) of the 17 HCV-RNA-positive cases was also higher (p<0.0001) than the negative cases (0.37+/-0.23). The cut-off value of ALT to distinguish the anti-HCV-positive from negative patients was 0.50% or 50% of the ULN (sensitivity=67%; specificity=83%). According to the HCV-RNA, the cut-off value of ALT was 0.45% or 45% of the ULN (sensitivity=71%; specificity=80%). CONCLUSION: Reducing the cut-off of ALT by half, enables a better identification of biochemical activity in patients with HCV infection on chronic HD. 相似文献
12.
Rupture of the ascending aorta is lethal in virtually all cases. In the recent literature, fewer than 9 cases of chronic, traumatic pseudoaneurysm of the ascending aorta have been documented. Reported herein is such a case, discovered incidentally and repaired successfully under cardiopulmonary bypass using a graft prosthesis. Aortogram remains the diagnostic method of choice in these patients. 相似文献
13.
14.
The adhesion of hematopoietic progenitor cells to bone marrow stromal cells is critical to hematopoiesis and involves multiple effector molecules. Stromal cell molecules that participate in this interaction were sought by analyzing the detergent-soluble membrane proteins of GBI/6 stromal cells that could be adsorbed by intact FDCP-1 progenitor cells. A single-chain protein from GBI/6 cells having an apparent molecular weight of 37 Kd was selectively adsorbed by FDCP-1 cells. This protein, designated p37, could be surface-radiolabeled and thus appeared to be exposed on the cell membrane. An apparently identical 37- Kd protein was expressed by three stromal cell lines, by Swiss 3T3 fibroblastic cells, and by FDCP-1 and FDCP-2 progenitor cells. p37 was selectively adsorbed from membrane lysates by a variety of murine hematopoietic cells, including erythrocytes, but not by human erythrocytes. Binding of p37 to cells was calcium-dependent, and was not affected by inhibitors of the hematopoietic homing receptor or the cell-binding or heparin-binding functions of fibronectin. It is proposed that p37 may be a novel adhesive molecule expressed on the surface of a variety of hematopoietic cells that could participate in both homotypic and heterotypic interactions of stromal and progenitor cells. 相似文献
15.
F. Teixeira Brandt C. D. Costa Albuquerque J. W. Barros Leal 《International urogynecology journal》1997,8(6):332-335
We report on the vaginal mucosal folds (VMF) at the urethral external meatus. Resection of the VMF reduces the dispersed micturition
and other urinary symptoms.
EDITORIAL COMMENT: The investigators describe the presence of a vaginal mucosal fold (VMF) just dorsal to the urethral meatus
and its relationship to voiding abnormalities. VMF were found on physical examination in 8.9% of the clinic population, all
of whom complained of dispersed micturition, and 79% also experienced other voiding abnormalities. The complaint of dispersed
micturition was successfully treated with excision of the VMF, and the other associated symptoms were improved. This structure
should be routinely looked for on physical examination, especially in patients with voiding symptoms. Only further investigation
of this newly described entity at other centers around the world will determine the incidence of the anatomic finding and
the prevalence of associated voiding disturbances across different populations. 相似文献
16.
Dorian Deshauer Anne Duffy Martin Alda Eva Grof Joy Albuquerque Paul Grof 《Revue canadienne de psychiatrie》2003,48(7):462-466
OBJECTIVE: A growing body of data suggests that a significantly enhanced salivary cortisol response to waking may indicate an enduring tendency to abnormal cortisol regulation. Our objective was to apply the response test to a population already known to have long-term hypothalamo-pituitary-adrenocortical (HPA) axis dysregulation. We hypothesized that the free cortisol response to waking, believed to be genetically influenced, would be elevated in a significant percentage of cases, regardless of the afternoon Dexamethasone Suppression Test (DST) value. METHOD: Using the free cortisol response to waking and the short daytime profile, we tested 18 clinically stable, lithium-responsive subjects from our long-term naturalistic follow-up of monthly DSTs. These tests include salivary testing every 15 minutes during the first hour of waking, followed by samples taken at 3:00 PM and 8:00 PM. RESULTS: While clinically stable on lithium prophylaxis, patients with bipolar disorder (BD) showed a significantly enhanced salivary cortisol response to waking, compared with control subjects (P < 0.03). Cortisol levels 30 minutes after waking significantly exceeded those in the large normative data provided in the literature (P < 0.001). CONCLUSIONS: Our observations support the hypothesis that the free cortisol response to waking can reflect relatively enduring HPA dysregulation, even when lithium-responsive BD patients are clinically well and their DSTs are normal. Because the test is easy to administer, the free cortisol response to waking may hold promise as a marker in studies of high-risk families predisposed to, or at risk for, mood disorders. 相似文献
17.
K S Rao J E Warnick J W Daly E X Albuquerque 《The Journal of pharmacology and experimental therapeutics》1987,243(2):775-783
The mechanism of the twitch potentiating action of pumiliotoxin-B (PTX-B), an indolizidine alkaloid from the skin of the frog Dendrobates pumilio, was studied on frog skeletal muscles. In the presence of PTX-B, a single stimulus to the muscle produced either a burst of repetitive action potentials superimposed on a depolarizing afterpotential or a single potential with a prolonged afterpotential at junctional as well as extrajunctional regions of the frog skeletal muscle fibers. The alkaloid did not cause repetitive activity in quiescent cells or spontaneous contractions. The duration of the burst of action potentials was related inversely and the amplitude and duration of postburst depolarizing after-potential was related directly to the concentration of PTX-B. The typical pattern of repetitive action potentials and postburst depolarization induced by PTX-B could be mimicked by depolarizing the muscle membrane with current pulses of long duration (150-470 ms). Lowering the external calcium or sodium concentration reduced the ability of PTX-B to initiate repetitive action potentials, whereas a low external chloride concentration had no effect. The frequency of MEPPs evoked by potassium, but not the spontaneous MEPP frequency, was increased by PTX-B, suggesting a selective effect on evoked transmitter release. PTX-B evoked repetitive EPPs in response to a single stimulus applied to the nerve, which was dependent upon the external calcium ion concentration. The amplitudes of EPPs in the train were facilitated, and their amplitude increased linearly at the lowest calcium concentration, but not at concentrations from 0.45 to 1.8 mM.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
18.
An inbred kindred with 15 cases of the autosomal recessive Ellis-van Creveld syndrome is reported. The ages of the 12 living affected varied between 3 and 82 years. The main characteristics include polydactyly of the hands and feet and several other skeletal anomalies, oral manifestations, and malformations of the heart in 50% of the living affected. 相似文献
19.
Nogueira SA Lambert JS Albuquerque AL Rodrigues R Reis S Bornia R Dias M Barbosa R Sztanjbock D Santos AL Blattner W Constantine NT 《Journal of human virology》2001,4(5):278-282
OBJECTIVES: To use two rapid human immunodeficiency virus (HIV) tests at labor, measure test acceptance and performance, and measure HIV prevalence in these women. METHODS: Between February and October 2000, two rapid tests (Determine; Abbott, Chicago, IL, U.S.A. and Double Check; Orgenics, Yavne, Israel) were used in three public maternities in Rio de Janeiro, Brazil. Enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) analysis confirmed positive and discordant results. RESULTS: Of the 858 patients who were enrolled, the mean gestational age was 36 weeks (median = 39, mode = 40) and 17 (2%) refused testing. Of the 841 patients tested, 13 were positive by both tests, which represents a 1.5% prevalence (95% confidence interval: 0.7%-2.3%); all were confirmed by ELISA and WB analysis. Seven samples gave discordant results by the rapid tests; of these, six were ELISA-negative/WB-negative and one was ELISA-negative/WB-indeterminate. The positive predictive value for samples that were positive by both rapid tests simultaneously was 100%. CONCLUSIONS: Two rapid HIV tests used at labor were well accepted (98%). When the combined results of the two rapid tests (but not a single rapid test) were analyzed, this strategy was as efficient as the standard ELISA and WB HIV strategy for correctly classifying individuals. 相似文献
20.
Mavale-Manuel S Alexandre F Duarte N Albuquerque O Scheinmann P Poisson-Salomon AS de Blic J 《Allergy》2004,59(4):388-393
BACKGROUND: Few studies have looked at risk factors for asthma in African children. We aimed to identify the risk factors associated with childhood asthma in Maputo (Mozambique). METHODS: This case-control study included 199 age-matched children (100 asthmatic and 99 nonasthmatic) who attended Maputo Central Hospital between January 1999 and July 2000. We collected information concerning their familial history of atopy, birth weight, environment and breast-feeding. Detailed information about morbidity and treatment was obtained for each asthmatic child. RESULTS: The children were aged between 18 months and 8 years; 60% were male. The asthmatic children were hospitalized more frequently than the nonasthmatic children (P < 0.0001). Most of the asthmatic children lived in the urban area of Maputo [odd ratio (OR) = 6.73, CI = 3.1-14.0, P < 0.0001], had a parental history of asthma (OR = 26.8, CI = 10.8-68.2, P < 0.0001) or rhinitis (OR = 4, CI = 1.2-13.3, P = 0.005), had at least parent who smoked and were weaned earlier than the nonasthmatic children (OR = 2.4, CI = 1.3-4.4, P < 0.001). CONCLUSION: Childhood asthma was strongly associated with a family history of asthma and rhinitis, the place of residence, having smokers as parents and early weaning from maternal breast milk. These results highlight the need to reassess the management of asthmatic children in Maputo. 相似文献